let shopArray = [
    {pCode: 2, pName: "面包", price: 4, num: 3},
    {pCode: 4, pName: "火腿", price: 2, num: 2},
    {pCode: 5, pName: "三明治", price: 5, num: 4},
    {pCode: 3, pName: "牛排", price: 20, num: 1},
    {pCode: 1, pName: "蛋糕", price: 8, num: 5}
];